Field Notice: Cisco 2620 and 2621 Clock and Timing Problems

April 15, 1999

Products Affected

Product

CISCO2620

CISCO2620-DC

CISCO2620-RPS

CISCO2621

CISCO2621-DC

CISCO2621-RPS

Problem Description

Cisco 2620 and 2621 units may have part of the system information programmed incorrectly. This information tells the Cisco IOS software the frequency of the clock on the main board. Cisco IOS software uses this to set up counters that drive all time based functions in the Cisco 2620 and 2621.

Background

This problem affects Cisco 2620 and Cisco 2621 units manufactured prior to March 19, 1999. This problem does not affect the Cisco 2610, Cisco 2611, Cisco 2612 or Cisco 2613.

Problem Symptoms

The symptoms of this problem fall into these categories:

Timing related functions. All software operations that rely on timing will be 25% fast. This includes time of day, routing tables updates, etc.

Clocking on the WAN Interface Card (WIC) interfaces. Serial interfaces configured for synchronous DCE mode will drive the clock 25% too fast (DTE mode is not affected). WIC async ports will use a baud rate 25% too fast (console, aux, and network module ports are not affected). Async applications will fail when using the WIC port.

Performance of the Network Timing Protocol (NTP) will be affected by this problem. The discrepency in the system clock will cause the NTP process to fail to sync up.